She said two of the four victims were female, and that none of the injuries were believed to be life-threatening.

Skid Row, an area occupying roughly 50 square blocks in downtown Los Angeles, has one of the highest concentrations of homeless people in the United States. It was not immediately known whether anyone involved in the shooting was homeless, Cervantes said.

Aerial video from a local television station KTLA-TV showed police patrol cars stopped next to a tent outside San Julian Park in downtown Los Angeles.

Paramedics were seen transporting one person onto an ambulance and treating another person who was sitting on a bench inside the park. Large sections of the streets were blocked off with police tape, video showed.

What appeared to be bullet casings were left on the ground, labeled by numbered police evidence markers. A pile of clothing was also laying on the ground at the crime scene, video showed.